One of the best places to dig—some say on the planet—for six different types of chalcedony.

This Gold Rush ghost town was once the subject of a territorial dispute between California and Nevada.

At the base of the Spring Mountains, a unique nursery packed with desert plants.

This ancient village provides insight into the complexity of the pre-Columbian Fremont Culture.

Tour a Cold War-era U.S. military missile launch site in Anchorage.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

The lasting remains of the region's once booming cement industry.

America's oldest drive-in movie theater has been in continuous operation since 1934.

One of Philadelphia's largest murals resides hidden under this bridge.

Instruments, apparatus, and rare books all relating to chemistry and its related sciences.

Take a stroll through this centuries-old tunnel of enormous moss-hung evergreens, nestled among the grounds of America’s first public sculpture garden.

The remains of a chapel created for convenience.

A ghost town that was wiped out by a flood in 1940.

The last remains of one of the oldest and largest oak trees in the United States calls this state park home.

This Asian-inspired tower in a lush urban park provides spectacular panoramic views of Baltimore.

Using a massive antenna made up of five miles of wire, two scientists tuned into organic radio waves from the planet Jupiter.

Historic barracks utilized during both the Revolutionary War and the Civil War.

The ruins of an 18th-century mansion that was once named "Mistake" by the man who had it built.

The world's oldest continuously operating airport was founded by the Wright Brothers.

America's first nuclear-powered merchant ship is now a time warp to the atomic age.

Fascinating museum dedicated to the under-appreciated medical history of urology features some wince-inducing devices.

Brain collection and database that narrows the gap between man and animal.

One of the oldest anatomical theaters in the U.S. still in use was once the site of an infamous cadaver riot.

A monumental statue of RCA's mascot now sits atop a historical society roof after a life of moving around.